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Electric Water Heater Sizing Calculator

Water Heater Sizing Formula:

\[ Size = Peak\,Demand \times 1.25 \]

gallons

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1. What is an Electric Water Heater Sizing Calculator?

Definition: This calculator determines the appropriate size (in gallons) of an electric water heater based on peak water demand and a safety factor.

Purpose: It helps homeowners and professionals select the right water heater capacity to meet household needs efficiently.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Size = Peak\,Demand \times Safety\,Factor \]

Where:

Explanation: The peak demand is multiplied by a safety factor to ensure adequate hot water supply during high usage periods.

3. Importance of Proper Water Heater Sizing

Details: Correct sizing prevents running out of hot water during peak usage while avoiding excessive energy costs from an oversized unit.

4. Using the Calculator

Tips: Enter your peak hot water demand in gallons and the desired safety factor (default 1.25). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine my peak demand?
A: Add up the hot water usage of all appliances/fixtures that might run simultaneously (shower, dishwasher, washing machine, etc.).

Q2: Why is the safety factor typically 1.25?
A: This 25% buffer accounts for variations in usage patterns and recovery rates.

Q3: When would I use a different safety factor?
A: Use higher factors (1.5) for large families or commercial applications, lower factors (1.1) for single users.

Q4: Does this work for tankless water heaters?
A: No, tankless units are sized by flow rate (GPM) and temperature rise needed.

Q5: How does recovery rate affect sizing?
A: Faster recovery units can sometimes be sized slightly smaller, but this calculator provides a conservative estimate.

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